Word Origincontr. superl. of proDefinitionfirst, chiefNASB Translationbefore (3), best (1), first (128), first of all (2), first importance (1), first man (1), first one (1), first things (1), first time (1), foremost (5), leading (2), leading man (1), leading men (5), outer (3), previous (1).

Thayer's Greek Lexicon

STRONGS NT 4413: πρῶτος

πρῶτος, πρώτη, πρῶτον (superlative of πρό, contracted from προατος, whence the Doric πρατός; the comparitive πρότερος see in its place) (from Homer down), the Sept. for רִאשׁון and often for אֶחַד and רֹאשׁ, first;

1. either in time or place, in any succession of things or of persons;

Matthew 26:17Adj-DFSGRK:Τῇ δὲ πρώτῃ τῶν ἀζύμωνNAS: Now on the first [day] of UnleavenedKJV: Now the first [day] of the [feast of] unleavened breadINT: on the moreover first [day] of the unleavened [bread]